Slider-operated rocking zipper for reclosable packaging

ABSTRACT

A reclosable package has a flexible zipper and a slider. The zipper comprises first and second zipper parts having interlocking elements, first opposing portions on one side of the interlocking elements and second opposing portions on the other side of the interlocking elements. The slider has a top wall, first and second side walls connected to the top wall, an opening end, a closing end, and first and second camming means that have respective fixed positional relationships to the first and second side walls and that cam the first opposing portions of lengthwise sections of the first and second zipper parts located inside the slider in opposite directions during movement of the slider in an opening direction along the zipper, while the second opposing portions of the lengthwise sections of the first and second zipper parts located inside the slider do not move further away from each other during the slider movement in the opening direction.

BACKGROUND OF THE INVENTION

[0001] This invention generally relates to slider-operated flexiblezippers for use in reclosable pouches, bags or other packages of thetype in which perishable material, such as foodstuff, may be stored.

[0002] Reclosable fastener assemblies are useful for sealingthermoplastic pouches or bags. Such fastener assemblies often include aplastic zipper and a slider. Typically, the plastic zippers include apair of interlockable fastener elements, or profiles, that form aclosure. As the slider moves across the profiles, the profiles areopened or closed. The profiles in plastic zippers can take on variousconfigurations, e.g. interlocking rib and groove elements havingso-called male and female profiles, interlocking alternating hook-shapedclosure elements, etc.

[0003] Conventional slider-operated zipper assemblies typically comprisea plastic zipper having two interlocking profiles and a slider foropening and closing the zipper. In one type of slider-operated zipperassembly, the slider straddles the zipper and has a separating finger atone end that is inserted between the profiles to force them apart as theslider is moved along the zipper in an opening direction. The other endof the slider is sufficiently narrow to force the profiles intoengagement and close the zipper when the slider is moved along thezipper in a closing direction.

[0004] Other types of slider-operated zipper assemblies avoid the use ofa separating finger. For example, U.S. Pat. No. 5,809,621 discloses aslider-operated zipper assembly wherein one zipper profile has a pair ofhandles that cooperate with the slider. As the slider is moved in anopening direction, the handles are squeezed together to disengage theprofiles. In U.S. Pat. No. 5,442,838, a slider-operated zipper assemblyis disclosed wherein the zipper profiles are engaged and disengaged inthe course of a “rolling action”. This “rolling action” is described asbeing achieved through cooperation between flanges on the profiles andshoulders which project inwardly from the arms of the slider. U.S. Pat.No. 6,047,450 discloses a zipper comprising a pair of mutuallyinterlockable profiled structures. The first profiled structurecomprises an interlocking element on a surface directed toward thesecond profiled structure and an integral base directed away from thesecond profiled structure. Likewise, the second profiled structurecomprises an interlocking element on a surface directed toward the firstprofiled structure and an integral base directed away from the firstprofiled structure. Additionally, portions of the two profiledstructures form a fulcrum about which the profiled structures may bepivoted out of engagement when lower edges of the bases are forcedtowards each other

[0005] In the case of sliders having a separating finger or post, it isusually necessary to have the finger or post extend into the productside of the package. Since the zipper halves are relatively rigid, theydo not conform to the shape of the post and a gap is left between thepost and the point where the zipper halves are fully mated. This gapcreates a potential for liquid and gas leakage from or into the package.From this standpoint, sliders without separating fingers or posts are animprovement.

[0006] There is a need for alternative designs of slider-operated zipperassemblies wherein a separating finger or post is not employed.

BRIEF DESCRIPTION OF THE INVENTION

[0007] The invention is directed to a slider-zipper assembly in whichthe slider cams the zipper open by spreading opposing portions of thezipper parts lying on one side of the interlocking elements, while theopposing portions of the zipper parts on the other side of theinterlocking elements do not move away from and preferably contact eachother.

[0008] One aspect of the invention is an assembly comprising a flexiblezipper and a slider mounted to the zipper. The zipper comprises a firstzipper part comprising a first interlockable element, a first portionextending on one side of the first interlockable element, and a secondportion extending on the other side of the first interlockable element,and a second zipper part comprising a second interlockable element, afirst portion extending on one side of the second interlockable element,and a second portion extending on the other side of the secondinterlockable element. The first and second interlockable elements aremutually interlockable. The first portions of the first and secondzipper parts are mutually opposed. Similarly, the second portions of thefirst and second zipper parts are mutually opposed. The slider comprisesfirst and second side walls, an opening end, a closing end, and firstand second surfaces that have respective fixed positional relationshipsto the first and second side walls, are in contact with the firstopposing portions of the first and second zipper parts respectively, andare divergent in a closing direction from the closing end to the openingend of the slider. The first opposing portions of lengthwise sections ofthe first and second zipper parts located inside the slider move furtheraway from each other as the slider is moved in an opening directionalong the zipper, while the second opposing portions of the lengthwisesections of the first and second zipper parts located inside the sliderdo not move further away from each other during the slider movement inthe opening direction.

[0009] Another aspect of the invention is an assembly comprising aflexible zipper and a slider mounted to the zipper. The zipper comprisesa first zipper part comprising a first interlockable element, a firstportion extending on one side of the first interlockable element, and asecond portion extending on the other side of the first interlockableelement, and a second zipper part comprising a second interlockableelement, a first portion extending on one side of the secondinterlockable element, and a second portion extending on the other sideof the second interlockable element. The first and second interlockableelements are mutually interlockable. The first portions of the first andsecond zipper parts are mutually opposed. Similarly, the second portionsof the first and second zipper parts are mutually opposed. The slidercomprises first and second side walls, an opening end, a closing end,and first and second camming means that have respective fixed positionalrelationships to the first and second side walls and that cam the firstopposing portions of lengthwise sections of the first and second zipperparts located inside the slider in opposite directions during movementof the slider in an opening direction along the zipper, while the secondopposing portions of the lengthwise sections of the first and secondzipper parts located inside the slider do not move further away fromeach other during the slider movement in the opening direction.

[0010] A further aspect of the invention is a reclosable packagecomprising a receptacle, a flexible zipper joined to said receptacle,and a slider mounted to said zipper. The zipper has a structure inaccordance with one of the aspects previously described. Likewise theslider has structure and function in accordance with one of the aspectspreviously described.

[0011] Yet another aspect of the invention is a zipper comprising firstand second zipper parts, wherein the first zipper part comprises aprofiled rib on a side confronting the second zipper part and a firstprofiled groove on a side facing outward, and the second zipper partcomprises a second profiled groove on a side confronting the firstzipper part and a third profiled groove on a side facing outward, theprofiled rib being interlocked with the second profiled groove. Thefirst and third profiled grooves are located at a first elevation andthe second profiled groove is located at a second elevation differentthan the first elevation when the first and second zipper parts areinterlocked.

[0012] A further aspect of the invention is a zipper comprising firstand second zipper parts, wherein the first zipper part comprises a firstprofiled rib on a side confronting the second zipper part and a secondprofiled rib on a side facing outward, and the second zipper partcomprises a profiled groove on a side confronting the first zipper partand a third profiled rib on a side facing outward, the first profiledrib being interlocked with the profiled groove. The second and thirdprofiled ribs are located at a first elevation and the first profiledrib is located at a second elevation different than the first elevationwhen the first and second zipper parts are interlocked.

[0013] Another aspect of the invention is a slider comprising a topwall, first and second side walls connected to the top wall andextending from an opening end to a closing end, and first and secondprofiled ribs respectively connected to and projecting from the interiorsurfaces of the first and second side walls. Each of the first andsecond profiled ribs comprises a respective enlarged head. The heads ofthe profiled ribs are divergent along at least a portion of the lengthof the slider in a direction from the opening end to the closing end.

[0014] An additional aspect of the invention is a slider comprising atop wall, first and second side walls connected to the top wall andextending from an opening end to a closing end, first and second bottomwalls respectively connected to the first and second side walls andprojecting generally inward, and a first and second projectionsrespectively connected to opposing ends of the first and second bottomwalls and projecting generally toward the top wall. The first and secondprojections are divergent along at least a portion of the length of theslider in a direction from the opening end to the closing end.

[0015] Other aspects of the invention are disclosed and claimed below.

BRIEF DESCRIPTION OF THE DRAWINGS

[0016]FIG. 1 is a schematic showing an isometric view of a reclosablepackage having a slider-operated flexible zipper.

[0017]FIGS. 2 and 3 are schematics showing opposing end views of aslider-zipper assembly in accordance with a first embodiment of theinvention. FIG. 2 shows the closing end of the slider (in dashed lines)and the closed zipper (in solid lines); FIG. 3 shows the opening end ofthe same slider (in dashed lines) and the opened zipper (in solidlines). [To facilitate the reader's understanding, the relationship ofthe male and female profiles have not been reversed in the second view.This is also true for FIGS. 4 and 5 and FIGS. 6 and 7.]

[0018]FIGS. 4 and 5 are schematics showing opposing end views of aslider-zipper assembly in accordance with a second embodiment of theinvention. FIG. 4 shows the closing end of the slider (in dashed lines)and the closed zipper (in solid lines); FIG. 5 shows the opening end ofthe same slider (in dashed lines) and the opened zipper (in solidlines).

[0019]FIGS. 6 and 7 are schematics showing opposing end views of aslider-zipper assembly in accordance with a third embodiment of theinvention. FIG. 6 shows the closing end of the slider (in dashed lines)and the closed zipper (in solid lines); FIG. 7 shows the opening end ofthe same slider (in dashed lines) and the opened zipper (in solidlines).

[0020]FIG. 8 is a schematic showing an end view of a slider-zipperassembly in accordance with a fourth embodiment of the invention. FIG. 8shows the closing end of the slider (in dashed lines) and the closedzipper (in solid lines).

DETAILED DESCRIPTION OF THE INVENTION

[0021] Reference will now be made to the drawings, in which similarelements in different drawings bear the same reference numerals. Areclosable bag 10 having a flexible plastic zipper 12 operated bymanipulation of a slider 14 is shown in FIG. 1. It should be understoodthat the slider-zipper assemblies disclosed herein can be installed in areclosable bag of the type shown in FIG. 1 or other types of reclosablepackages having different structures.

[0022] Still referring to FIG. 1, the bag 10 may be made from anysuitable sheet material or plastic film and comprises opposite wallpanels, which may be secured together at opposite side edges of the bagby seams (not shown). The opposing bottoms of the wall panels may bejoined, for example, by means of a heat seal made in conventionalfashion, e.g., by application of heat and pressure or ultrasonic energy.Typically, however, the bottom of the package is formed by a fold in theoriginal packaging film. Optionally, the bag may be provided with sidegussets having respective junctures with the front and rear wall panels.In the latter case, the bag may also be provided with a bottom panelhaving respective junctures with the front and rear wall panels and withthe side gussets.

[0023] At its top end, the bag 10 has an openable mouth, on the insideof which is an extruded plastic zipper 12. The zipper 12 comprises apair of interlockable fastener strips or zipper halves. The profiles ofthe zipper halves may take any form. For example, the zipper maycomprise interlocking rib and groove elements or alternating hook-shapedclosure elements. The preferred zipper material is polyethylene.

[0024] The front and rear bag wall panels are respectively sealed to thezipper halves 16 and 18 by heat fusion or welding. Alternatively, theinterlockable zipper halves can be attached to the wall panels byadhesive or bonding strips or the zipper profiles can be extrudedintegrally with the bag material. For the purpose of joinder, eachzipper half may be provided with a respective extension flange, to whichan upper portion of the respective bag wall panel is fused or welded.The walls of the bag may be formed of various types of thermoplasticmaterial, such as low-density polyethylene, substantially linearcopolymers of ethylene and a C3-C8 alpha-olefin, polypropylene,polyvinylidene chloride, mixtures of two or more of these polymers, ormixtures of one of these polymers with another thermoplastic polymer.The person skilled in the art will recognize that this list of suitablematerials is not exhaustive.

[0025] In zippered bags with sliders, as the slider moves across thezipper, the zipper is opened or closed. As shown in FIG. 1, the slideris slidable along the zipper in a closing direction “C”, causing thezipper halves to become engaged, or in an opening direction “O”, causingthe zipper halves to become disengaged.

[0026] The slider for opening or closing the reclosable zipper isgenerally shaped so that the slider straddles the zipper profiles. Theends of the slider are open to allow the zipper to pass through. Theslider may be made in multiple parts and welded together or the partsmay be constructed to be snapped together. The slider may also be ofone-piece construction. The slider can be made using any desired method,such as injection molding. The slider can be molded from any suitableplastic, such as nylon, polypropylene, polystyrene, acetal, polyketone,polybutylene terephthalate, high-density polyethylene, polycarbonate, orABS.

[0027] A bag incorporating a zipper and a slider preferably includesmeans, such as end stops (not shown in FIG. 1), for preventing theslider from sliding off the end of the zipper when the slider reachesthe closed or fully opened position. Such end stops perform dualfunctions, serving as stops to prevent the slider from going off the endof the zipper and also holding the two zipper profiles together toprevent the bag from opening in response to stresses applied to theprofiles through normal use of the bag. The end stops may, for example,comprise stomped areas on the zipper profiles themselves, riveted endclamps, plastic end clips fused to the zipper, or any other suitablestructure. The stomped end stops can be sections of the profiles thatare fused together proximate to the open and closed slider positionssuch that the end stops are raised. Stomping can be carried out by, forexample, applying heat and/or pressure or using ultrasonic methods.

[0028] The zipper halves preferably comprise interlocking rib and grooveelements, which are well known in the art. Many configurations of riband groove elements may be employed to perform any one of a number ofrequired functions. For instance, specific rib and groove elements maybe employed to permit the package to be more easily opened from theoutside than from the inside, so that the tension produced by thecontents of the package will not accidentally open the rib and grooveelements. The rib and groove elements may be carefully formed of a softflexible material in part thereof so that the contents of the packageare in fact relatively hermetically sealed from the outside.

[0029]FIGS. 2 and 3 show cross-sectional views of a zipper in accordancewith a first embodiment of the present invention. A slider 14 a is shownin dashed lines. The closing end of the slider 14 a is shown in FIG. 2;the opening end of the slider 14 a is shown in FIG. 3. The zipper isshown in FIG. 2 in a closed state with zipper halves interlocked; thezipper is shown in FIG. 3 in an opened state with the zipper halvesdisengaged. The zipper comprises first and second fastener strips orzipper halves 16 a and 18 a. Each zipper half is preferably made byextruded thermoplastic material to form a strip with a constant profile.The first zipper half 16 a comprises an interlockable profiled element24 having a male profile and an extension flange 20; the second zipperhalf 18 a comprises an interlockable profiled portion 26 (see FIG. 3)having a female profile and an extension flange 22. The front and rearwall panels of the bag 10 are respectively joined to the extensionflanges 20 and 22. The male and female profiles may be configured andsized with tolerances sufficiently close to ensure a liquid-tightinterlock between the profiles.

[0030] In accordance with the embodiment depicted in FIGS. 2 and 3, thelower portion of zipper half 16 a is formed with a longitudinal groove32 and the lower portion of the zipper half 18 a is formed with alongitudinal groove 34. The grooves 32 and 34 face outward on oppositesides of the closed zipper. Each groove 32, 34 has a profile shaped toreceive a respective rib 28, 30 extending inwardly from the side wallsof the slider 14 a. Each of ribs 28, 30 has a detent or hook projectinggenerally transverse to the rib at the rib's distal portion. Thedetents, in cooperation with the form-fitting profiled grooves 32, 34,serve to latch the zipper halves 16 a, 18 a to the opposing side wallsof the slider 14 a. Preferably, the ribs 28 and 30 extend longitudinallythe length of the slider. The slider 14 a is designed with side wallshaving portions that diverge in the direction from the closing end ofthe slider to the opening end of the slider. Similarly, the ribs 28 and30 diverge in the same direction. As a result of slider movement in theopening direction, the zipper halves are separated along those zippersegments traversed by the slider, or at least traversed by that portionof the slider which carries the diverging segments of ribs 28, 30.Because the lower portions of the zipper halves 16 a, 18 a are latchedto the slider 14 a by the diverging ribs 28, 30, during slider movementin the opening direction the lower portions of the zipper halves arepulled apart by the slider until the zipper profiles 24 and 26 aredisengaged, i.e., no longer interlocked. The corners at the tops of thezipper halves are preferably rounded. These rounded corners arepreferably in rocking contact during spreading open of the zipper by theslider.

[0031] The force that opens the zipper in the embodiment shown in FIGS.2 and 3 is applied by those surfaces of the ribs 28 and 30 that face theopposing internal surfaces of the slider side walls, namely, theundersurfaces of the detents of ribs 28, 30. A person skilled in the artwill recognize that the ribs 28, 30 can have profiles different thanthose depicted in FIGS. 2 and 3, as long as the ribs have latchingsurfaces to abut and press against the zipper halves to spread themapart as the slider side walls diverge relative to the zipper. Forexample, ribs 28 and 30 could have detents on opposing sides of thestem, i.e., in the shape of an arrowhead.

[0032]FIGS. 4 and 5 show cross-sectional views of a zipper in accordancewith a second embodiment of the present invention. A slider 14 b isshown in dashed lines. The closing end of the slider 14 b is shown inFIG. 4; the opening end of the slider 14 b is shown in FIG. 5. Thezipper is shown in FIG. 4 in a closed state with zipper halvesinterlocked; the zipper is shown in FIG. 5 in an opened state with thezipper halves disengaged. The zipper comprises first and second fastenerstrips or zipper halves 16 b and 18 b. Again, each zipper half ispreferably made by extruding thermoplastic material to form a strip witha constant profile. The first zipper half 16 b comprises aninterlockable profiled element 24 having a male profile and an extensionflange 20; the second zipper half 18 b comprises an interlockableprofiled portion 26 (see FIG. 5) having a female profile and anextension flange 22. The front and rear wall panels of the bag 10 arerespectively joined to the extension flanges 20 and 22. The male andfemale profiles may be configured and sized with tolerances sufficientlyclose to ensure a liquid-tight interlock between the profiles.

[0033] In accordance with the embodiment depicted in FIGS. 4 and 5, theupper portion of the zipper half 16 b is formed with a longitudinalgroove 32 and the upper portion of the zipper half 18 b is formed with alongitudinal groove 34. The grooves 32 and 34 face outward on oppositesides of the closed zipper. Each groove 32, 34 has a profile shaped toreceive a respective rib 28, 30 extending inwardly from the side wallsof the slider 14 b. Each of ribs 28, 30 has a detent or hook projectinggenerally transverse to the rib at the rib's distal portion. Thedetents, in cooperation with the form-fitting profiled grooves 32, 34,serve to latch the zipper halves 16 b, 18 b to the opposing side wallsof the slider 14 b. Preferably, the ribs 28 and 30 extend longitudinallythe length of the slider. Although ribs 28 and 30 are shown as having adetent on one side, these ribs may instead be T-shaped with detents onboth sides. The use of T-shaped ribs is desirable in the case where theslider is threaded onto the zipper from one end, in which case it wouldbe preferable to have a rib profile that cannot be pulled out of thezipper profile during slider camming action. However, if the slider isside loaded and the slider ribs are pushed into the outside zippergrooves, then a rib profile with only one detent is preferred. Theinterlocking zipper elements should be designed to disengage from eachother before the slider elements disengage from the zipper.

[0034] The slider 14 b is designed with side walls having portions thatdiverge in the direction from the closing end of the slider to theopening end of the slider. Similarly, the ribs 28 and 30 diverge in thesame direction. As a result of slider movement in the opening direction,the zipper halves are separated along those zipper segments traversed bythe slider, or at least traversed by that portion of the slider whichcarries the diverging segments of ribs 28, 30. Because the zipper halves16 b, 18 b are latched to the diverging ribs 28, 30 of the slider,during slider movement in the opening direction the upper portions ofthe zipper halves are pulled apart by the slider until the zipperprofiles 24 and 26 are disengaged, i.e., no longer interlocked. Theopposing corners at the bottoms of the zipper halves are preferably inrocking contact during spreading open of the zipper by the slider.

[0035]FIGS. 6 and 7 show cross-sectional views of a zipper in accordancewith a third embodiment of the present invention. A slider 14 c is shownin dashed lines. The closing end of the slider 14 c is shown in FIG. 6;the opening end of the slider 14 c is shown in FIG. 7. The zipper isshown in FIG. 6 in a closed state with zipper halves interlocked; thezipper is shown in FIG. 7 in an opened state with the zipper halvesdisengaged. The zipper comprises first and second fastener strips orzipper halves 16 c and 18 c. The first zipper half 16 c comprises aninterlockable profiled element 24 and no extension flange; the secondzipper half 18 c comprises an interlockable profiled portion 26 (seeFIG. 7) having a female profile and no extension flange. The front andrear wall panels of the bag 10 are respectively joined to the zipperhalves 16 c and 18 c. The bag and zipper could be extruded together, orthe zipper could be extruded and then applied to the bag film.Alternatively, the zipper halves could be provided with extensionflanges, to which the bag walls are joined.

[0036] In accordance with the embodiment depicted in FIGS. 6 and 7, theslider 14 c comprises a top wall 34, a pair of side walls 36 and 38connected to the top wall 34, a pair of bottom walls 40 and 42respectively connected to the side walls 36 and 38, and a pair ofupwardly directed projections 44 and 46 respectively connected to thebottom walls 40 and 42. In accordance with the third embodiment, theside wall 36 and opposing upward projection 44 define a recess in whicha bottom portion of the zipper half 16 c is seated with little play,while the side wall 38 and opposing upward projection 46 define a recessin which a bottom portion of the zipper half 18 c is seated with littleplay. Preferably the slider has a monolithic construction. The preferredmethod of manufacture is injection molding.

[0037] As seen in FIG. 6, the zipper passes through the closing end ofthe slider with little play. In particular, the bottom portions of thezipper halves are effectively latched to the slider side walls by meansof the upward projections 44 and 46. In accordance with the thirdembodiment, the side walls 36 and 38 diverge along the slider length inthe direction from the closing end to the opening end of the slider. Theside walls are shown with maximum divergence in FIG. 7. As the sidewalls diverge, the bottom walls 40, 42 and the upward projections 44, 46maintain the same spatial relationship to the side walls. Since theupward projections 44 and 46 effectively latch the zipper halves 16 cand 18 c to the slider side walls, as the side walls diverge, so do thelower portions of the zipper halves. In other words, as the slider movesin the opening direction, the divergent projections 44 and 46 cause thelower portions of the zipper halves to spread apart, thereby prying openthe zipper, as seen in FIG. 7. Again, the opposing top corners of thezipper halves 16 c, 18 c are preferably in abutment with each other asthe lower portions of the zipper halves are pulled apart.

[0038] The force that opens the zipper in the embodiment shown in FIGS.6 and 7 is applied by those surfaces of the projections 44, 46 that facethe opposing internal surfaces of the slider side walls and that are incontact with the confronting surfaces of the zipper halves. A personskilled in the art will recognize that the projections can have profilesdifferent than those depicted in FIGS. 6 and 7, as long as theprojections have latching surfaces to abut and press against the zipperhalves to spread them apart as the slider side walls diverge relative tothe zipper.

[0039] One such different profile is shown in FIG. 8. In this fourthembodiment, the bottoms of the zipper halves have chamfers 52 and 54respectively, while the projections 48 and 50 have triangular profilesinstead of rectangular profiles. The chamfers and triangular projectionsare matched so that the projections again effectively latch the bottomsof the zipper halves to the slider side walls. Although the opening endof the slider 14 d is not shown, it will be readily understood that thebottoms of the zipper halves 16 d and 18 d will be pulled apart when theside walls 36 and 38 diverge, thereby disengaging the male profile 24from the female profile.

[0040] A person skilled in the art will further recognize that thebottom portions of the zipper halves may be provided with recesses thatreceive and interlock with respective form-fitting projectionsprojecting upward from the bottom walls of the slider. The recesses inthe bottoms of the zipper halves may comprise grooves that are V-shaped,U-shaped, etc. In accordance with a further alternative embodiment, therecesses could each have a female profile while the projections eachhave a male profile, or the recesses and projections could have profilessimilar to those of ribs 28, 30 and grooves 32, 34 depicted in FIGS. 2and 3, with the difference that the rib/groove coupling is made at thebottoms of the zipper halves as opposed to along the sides.

[0041] Although in each of the embodiments disclosed above, the femalezipper half takes the form of a recess in a relatively thick strip, itis well-known to manufacture a female zipper member in the form of apair of legs in a U-shaped arrangement projecting from a relatively thinstrip, the legs having inwardly directed detents or hooks for latchingbehind and holding the detents or hooks of the inserted male profile. Asa further alternative, both interlocking profiles may comprisealternating interleaved hook-shaped closure elements similar in profileinstead of male/female profiles. Also, it will be obvious to a personskilled in the art that a rib may be continuous or may havediscontinuities. In other words, as used herein, the term “rib”encompasses both a continuous profiled rib member and a series of spacedprofiled rib elements. The same is true for the term “projection.”

[0042] While the invention has been described with reference to variousembodiments, it will be understood by those skilled in the art thatvarious changes may be made and equivalents may be substituted forelements thereof without departing from the scope of the invention. Forexample, although the first and second embodiments disclosed above arearranged so that the slider has diverging ribs or projections and thezipper profiles have form-fitting grooves, it would be equivalent toform the slider with diverging form-fitting profiled grooves, while thezipper halves have ribs or projections interlocked with the grooves onthe slider. Also, it should be apparent to persons skilled in the artthat the camming ribs and camming projections disclosed herein need notbe continuously, but instead may be formed as a series of spaced apartrib sections. In addition, many modifications may be made to adapt aparticular situation to the teachings of the invention without departingfrom the essential scope thereof. Therefore it is intended that theinvention not be limited to the particular embodiment disclosed as thebest mode contemplated for carrying out this invention, but that theinvention will include all embodiments falling within the scope of theappended claims.

[0043] As used in the claims, the term “package” means a container, bag,pouch or other receptacle for objects, material or stuff. A container,bag, pouch or other receptacle is deemed to be a package even if not yetpacked with objects, material or stuff. As used in the claims, the verb“joined” means fused, bonded, sealed, adhered, etc., whether byapplication of heat and/or pressure, application of ultrasonic energy,application of a layer of adhesive material or bonding agent,interposition of an adhesive or bonding strip, etc. As used in theclaims, the term “rib” means a rib that is continuous or comprises aseries of spaced-apart rib sections. Similarly, as used in the claims,the term “projection” means a projection that is continuous or comprisesa series of spaced-apart projecting sections

1. An assembly comprising a flexible zipper and a slider mounted to saidzipper, wherein: said zipper comprises a first zipper part comprising afirst interlockable element, a first portion extending on one side ofsaid first interlockable element, and a second portion extending on theother side of said first interlockable element, and a second zipper partcomprising a second interlockable element, a first portion extending onone side of said second interlockable element, and a second portionextending on the other side of said second interlockable element, saidfirst and second interlockable elements being mutually interlockable,said first portions of said first and second zipper parts being mutuallyopposed, and said second portions of said first and second zipper partsbeing mutually opposed; and said slider comprises first and second sidewalls, an opening end, a closing end, and first and second surfaces thathave respective fixed positional relationships to said first and secondside walls, are in contact with said first opposing portions of saidfirst and second zipper parts respectively, and are divergent in aclosing direction from said closing end to said opening end of saidslider, whereby said first opposing portions of lengthwise sections ofsaid first and second zipper parts located inside said slider movefurther away from each other as said slider is moved in an openingdirection along said zipper, while said second opposing portions of saidlengthwise sections of said first and second zipper parts located insidesaid slider do not move further away from each other during said slidermovement in said opening direction.
 2. The assembly as recited in claim1, wherein said slider further comprises a top wall connected to saidfirst and second side walls, said first opposing portions of said firstand second zipper parts being disposed between said top wall of saidslider and said first and second interlockable elements of said firstand second zipper parts.
 3. The assembly as recited in claim 1, whereinsaid slider further comprises a top wall connected to said first andsecond side walls, said second opposing portions of said first andsecond zipper parts being disposed between said top wall of said sliderand said first and second interlockable elements of said first andsecond zipper parts.
 4. The assembly as recited in claim 1, wherein saidfirst zipper part comprises a first groove and said second zipper partcomprises a second groove, further comprising first and second ribsrespectively connected to opposing interior surfaces of said first andsecond side walls and respectively interlocked with said first andsecond grooves, said first and second ribs respectively comprising firstand second detents, wherein said first surface comprises an undersurfaceof said first detent and said second surface comprises an undersurfaceof said second detent.
 5. The assembly as recited in claim 1, whereinsaid first side wall comprises a first groove and said second side wallcomprises a second groove, further comprising first and second ribsrespectively connected to opposing exterior surfaces of said first andsecond zipper parts and respectively interlocked with said first andsecond grooves, said first and second ribs respectively comprising firstand second detents, wherein said first surface comprises an interiorsurface of said first groove that is disposed behind said first detentand said second surface comprises an interior surface of said secondgroove that is disposed behind said second detent.
 6. The assembly asrecited in claim 3, wherein said slider further comprises first andsecond bottom walls respectively connected to said first and second sidewalls, and first and second projections respectively connected to saidfirst and second bottom walls, said first and second projectionsprojecting toward said top wall of said slider, wherein said firstsurface comprises a surface of said first projection and said secondsurface comprises a surface of said second projection.
 7. The assemblyas recited in claim 6, wherein said first and second projections projectinto a space between opposing distal portions of said first opposingportions of said first and second zipper parts.
 8. The assembly asrecited in claim 6, wherein said first and second zipper partsrespectively comprise first and second recesses, and said first andsecond projections respectively project into said first and secondrecesses.
 9. The assembly as recited in claim 3, wherein said first andsecond zipper parts respectively further comprise first and secondextension flanges that extend away from said top wall of said slider.10. A package comprising a receptacle, a flexible zipper joined to saidreceptacle, and a slider mounted to said zipper, wherein: said zippercomprises a first zipper part comprising a first interlockable element,a first portion extending on one side of said first interlockableelement, and a second portion extending on the other side of said firstinterlockable element, and a second zipper part comprising a secondinterlockable element, a first portion extending on one side of saidsecond interlockable element, and a second portion extending on theother side of said second interlockable element, said first and secondinterlockable elements being mutually interlockable, said first portionsof said first and second zipper parts being mutually opposed, and saidsecond portions of said first and second zipper parts being mutuallyopposed; and said slider comprises first and second side walls, anopening end, a closing end, and first and second surfaces that haverespective fixed positional relationships to said first and second sidewalls, are in contact with said first opposing portions of said firstand second zipper parts respectively, and are divergent in a closingdirection from said closing end to said opening end of said slider,whereby said first opposing portions of lengthwise sections of saidfirst and second zipper parts located inside said slider move furtheraway from each other as said slider is moved in an opening directionalong said zipper, while said second opposing portions of saidlengthwise sections of said first and second zipper parts located insidesaid slider do not move further away from each other during said slidermovement in said opening direction.
 11. The package as recited in claim10, wherein said slider further comprises a top wall connected to saidfirst and second side walls, said first opposing portions of said firstand second zipper parts being disposed between said top wall of saidslider and said first and second interlockable elements of said firstand second zipper parts.
 12. The package as recited in claim 10, whereinsaid slider further comprises a top wall connected to said first andsecond side walls, said second opposing portions of said first andsecond zipper parts being disposed between said top wall of said sliderand said first and second interlockable elements of said first andsecond zipper parts.
 13. The package as recited in claim 10, whereinsaid first zipper part comprises a first groove and said second zipperpart comprises a second groove, further comprising first and second ribsrespectively connected to opposing interior surfaces of said first andsecond side walls and respectively interlocked with said first andsecond grooves, said first and second ribs respectively comprising firstand second detents, wherein said first surface comprises an undersurfaceof said first detent and said second surface comprises an undersurfaceof said second detent.
 14. The package as recited in claim 10, whereinsaid first side wall comprises a first groove and said second side wallcomprises a second groove, further comprising first and second ribsrespectively connected to opposing exterior surfaces of said first andsecond zipper parts and respectively interlocked with said first andsecond grooves, said first and second ribs respectively comprising firstand second detents, wherein said first surface comprises an interiorsurface of said first groove that is disposed behind said first detentand said second surface comprises an interior surface of said secondgroove that is disposed behind said second detent.
 15. The package asrecited in claim 12, wherein said slider further comprises first andsecond bottom walls respectively connected to said first and second sidewalls, and first and second projections respectively connected to saidfirst and second bottom walls, said first and second projectionsprojecting toward said top wall of said slider, wherein said firstsurface comprises a surface of said first projection and said secondsurface comprises a surface of said second projection.
 16. The packageas recited in claim 15, wherein said first and second projectionsproject into a space between opposing distal portions of said firstopposing portions of said first and second zipper parts.
 17. The packageas recited in claim 15, wherein said first and second zipper partsrespectively comprise first and second recesses, and said first andsecond projections respectively project into said first and secondrecesses.
 18. The package as recited in claim 12, wherein said first andsecond zipper parts respectively further comprise first and secondextension flanges that extend away from said top wall of said slider,said receptacle being joined to said first and second extension flanges.19. An assembly comprising a flexible zipper and a slider mounted tosaid zipper, wherein: said zipper comprises a first zipper partcomprising a first interlockable element, a first portion extending onone side of said first interlockable element, and a second portionextending on the other side of said first interlockable element, and asecond zipper part comprising a second interlockable element, a firstportion extending on one side of said second interlockable element, anda second portion extending on the other side of said secondinterlockable element, said first and second interlockable elementsbeing mutually interlockable, said first portions of said first andsecond zipper parts being mutually opposed, and said second portions ofsaid first and second zipper parts being mutually opposed; and saidslider comprises first and second side walls, an opening end, a closingend, and first and second camming means that have respective fixedpositional relationships to said first and second side walls and thatcam said first opposing portions of lengthwise sections of said firstand second zipper parts located inside said slider in oppositedirections during movement of said slider in an opening direction alongsaid zipper, while said second opposing portions of said lengthwisesections of said first and second zipper parts located inside saidslider do not move further away from each other during said slidermovement in said opening direction.
 20. The assembly as recited in claim19, wherein said slider further comprises a top wall connected to saidfirst and second side walls, said first opposing portions of said firstand second zipper parts being disposed between said top wall of saidslider and said first and second interlockable elements of said firstand second zipper parts.
 21. The assembly as recited in claim 19,wherein said slider further comprises a top wall connected to said firstand second side walls, said second opposing portions of said first andsecond zipper parts being disposed between said top wall of said sliderand said first and second interlockable elements of said first andsecond zipper parts.
 22. A package comprising a receptacle, a flexiblezipper joined to said receptacle, and a slider mounted to said zipper,wherein: said zipper comprises a first zipper part comprising a firstinterlockable element, a first portion extending on one side of saidfirst interlockable element, and a second portion extending on the otherside of said first interlockable element, and a second zipper partcomprising a second interlockable element, a first portion extending onone side of said second interlockable element, and a second portionextending on the other side of said second interlockable element, saidfirst and second interlockable elements being mutually interlockable,said first portions of said first and second zipper parts being mutuallyopposed, and said second portions of said first and second zipper partsbeing mutually opposed; and said slider comprises first and second sidewalls, an opening end, a closing end, and first and second camming meansthat have respective fixed positional relationships to said first andsecond side walls and that cam said first opposing portions oflengthwise sections of said first and second zipper parts located insidesaid slider in opposite directions during movement of said slider in anopening direction along said zipper, while said second opposing portionsof said lengthwise sections of said first and second zipper partslocated inside said slider do not move further away from each otherduring said slider movement in said opening direction.
 23. The packageas recited in claim 22, wherein said slider further comprises a top wallconnected to said first and second side walls, said first opposingportions of said first and second zipper parts being disposed betweensaid top wall of said slider and said first and second interlockableelements of said first and second zipper parts.
 24. The package asrecited in claim 22, wherein said slider further comprises a top wallconnected to said first and second side walls, said second opposingportions of said first and second zipper parts being disposed betweensaid top wall of said slider and said first and second interlockableelements of said first and second zipper parts.
 25. The package asrecited in claim 22, wherein said first and second zipper partsrespectively further comprise first and second extension flanges thatextend away from said top wall of said slider, said receptacle beingjoined to said first and second extension flanges.
 26. A zippercomprising first and second zipper parts, wherein said first zipper partcomprises a profiled rib on a side confronting said second zipper partand a first profiled groove on a side facing outward, and said secondzipper part comprises a second profiled groove on a side confrontingsaid first zipper part and a third profiled groove on a side facingoutward, said profiled rib being interlocked with said second profiledgroove, said first and third profiled grooves being located at a firstelevation and said second profiled groove being located at a secondelevation different than said first elevation when said first and secondzipper parts are interlocked.
 27. A zipper comprising first and secondzipper parts, wherein said first zipper part comprises a first profiledrib on a side confronting said second zipper part and a second profiledrib on a side facing outward, and said second zipper part comprises aprofiled groove on a side confronting said first zipper part and a thirdprofiled rib on a side facing outward, said first profiled rib beinginterlocked with said profiled groove, said second and third profiledribs being located at a first elevation and said first profiled ribbeing located at a second elevation different than said first elevationwhen said first and second zipper parts are interlocked.
 28. A slidercomprising a top wall, first and second side walls connected to said topwall and extending from an opening end to a closing end, and first andsecond profiled ribs respectively connected to and projecting from theinterior surfaces of said first and second side walls, each of saidfirst and second profiled ribs comprising a respective enlarged head,wherein said heads of said profiled ribs are divergent along at least aportion of the length of said slider in a direction from said openingend to said closing end.
 29. A slider comprising a top wall, first andsecond side walls connected to said top wall and extending from anopening end to a closing end, first and second bottom walls respectivelyconnected to said first and second side walls and projecting generallyinward, and a first and second projections respectively connected toopposing ends of said first and second bottom walls and projectinggenerally toward said top wall, wherein said first and secondprojections are divergent along at least a portion of the length of saidslider in a direction from said opening end to said closing end.